Monitoring performance of computing systems

ABSTRACT

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for monitoring performance of computing systems. In some implementations, a set of tasks for a server system to perform is identified. Multiple performance testing cycles are performed, in which each of the performance testing cycles includes: sending, for each task in the set of tasks, a request for the server system to perform the task; receiving a response from the server system for each of the requests, and storing a performance measure for each of the tasks based on the response received from the server system for the task. Based on the performance measures for the multiple performance testing cycles, an evaluation is performed whether conditions are satisfied for adjusting one or more operating parameters of the server system or for providing a notification regarding the operation of the server system.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No. 16/556,636, filed Aug. 30, 2019, now allowed, which is incorporated by reference.

TECHNICAL FIELD

The present specification relates to monitoring performance of computer systems.

BACKGROUND

Various techniques are used to test computer systems. However, many testing methods do not effectively indicate the experience of an end-user actually experiences.

SUMMARY

In some implementations, a computer system can perform ongoing performance testing of other computer systems, such as server systems, to monitor the quality of experience that is provided to end users. For example, a management system can run a headless web browser and issue requests to a server in a way that simulates users making requests to the server. The management system determines the server's response time for each request (e.g., the duration from the time of the request to the time of the server's response that fulfills the request). This allows the management system to measure the amount of delay that a user would experience after making a request to the server. This type of testing can be performed for a variety of types of tasks, and can be done repeatedly to maintain an ongoing, up-to-date measure of the level of performance of the server. In many cases, the ongoing stream of response time information obtained in this way can serve as a “heartbeat” or substantially real-time and continually refreshed measure of the status of the server.

The requests that the management system sends for monitoring purposes can be requests to perform the same types of actions or tasks that actual users commonly request, such as running reports, generating documents, loading a data cube, processing a query, and so on. The management system may automatically select the tasks for monitoring from usage logs or other data about how users interact with a computer system over time. The tasks used for monitoring can re-create specific actions and tasks that users have actually performed. For example, the requests to a server may be to load each of the 10 documents most frequently accessed by users over a time period, such as the previous week. As another example, a request might be to run a query identified from usage logs as being issued frequently by users. The monitoring system can automatically select the tasks to perform for monitoring purposes, for example, to include the most commonly performed actions of different types. As another example, the monitoring system may determine the set of tasks to be performed based on a predetermined signal or input from an administrator. For example, an administrator my specify specific reports or documents whose loading performance should be monitored, by placing the reports in a specific folder, listing the reports in a user interface or file, using a naming convention for the reports that signals whether performance is to be monitored, and so on. In other cases, a user may specify that all reports in a particular library or all reports available to a server should be monitored.

To further the goal of measuring performance experienced by end users, the monitoring system may perform tasks that represent different aspects that rely on a server system to be monitored. As an example, one task used for monitoring may be to generate a particular document. Another task used for monitoring may be to navigate to a particular portion within the document. Another task used for monitoring may be to enter filter criteria and apply the filter criteria to the document. As another example, processing a query to return results may be another task used for monitoring. Any task or action that relies on processing by the server may be instructed to be performed and the performance of the server (e.g., the length of time until the server completes the action) for the task monitored.

To carry out the performance monitoring, the management server can schedule tasks to run continually on monitored servers. This can involve requesting a server to perform monitoring tasks periodically, for example, by sending requests at regular intervals such as every minute, every 5 minutes, every 15 minutes, etc. The management server may select a set of tasks to monitor, and then may use a headless browser to request a monitored server to initiate each of the selected tasks at each interval. In some implementations, the management server issues the request for each task one-by-one in sequence, so that the server responds to the current monitored task before the management server requests the next monitoring task be performed. The management server can repeat the same series of tasks multiple times, and in some cases may initiate another round of performing the monitoring tasks as soon as the current round of performing the monitoring tasks is finished. The set of tasks to be monitored can be adjusted or changed by the management server from time to time.

The management system can use the ongoing performance measurements to perform various management functions. For example, the management system can use the series of performance measures to determine a baseline range of performance for a server. The management system can also compare current or recent performance measures to this baseline and detect deviations in run-time performance. When response times deviate from typical levels for at least a threshold amount or over at least a threshold amount of time, the management system can automatically take an action, such as notifying an administrator. The management system can additionally or alternatively take corrective action to a performance decrease, such as instructing a change to settings of the server being monitored, allocating additional hardware resources to the server, starting another instance of a server environment to better manage traffic, and so on.

In general, the management system can evaluate whether performance measures obtained through the ongoing monitoring satisfy certain conditions. The management server can then perform one or more actions that have been specified to correspond to the satisfied conditions. For example, the management server may assess a series of multiple performance measures representing performance data points measured over a time period. The management server can detect values, trends, or patterns that are indicative of certain operating conditions, such as excessive load or decrease in performance experienced by users.

Because each cycle of performance measurement involves multiple different tasks, the management system can detect performance problems of different types. For example, if the loading of ten different documents is monitored and a performance measurement cycle shows most or all exhibiting a loading time that is longer than typical, then the management server can determine that performance is decreasing generally for the server. By contrast, if only a specific document shows decreased performance, the management server may determine that a problem exists for the specific document and potentially the component elements or data sources the document relies on. This can help narrow down the causes of performance decreases and also select corrective actions to improve performance. Similarly, some operations may be more sensitive to memory availability while other tasks are more affected by CPU availability, and by detecting the differences as the performance levels of each, the management system can identify which aspect is under greatest constraint.

In one general aspect, a method performed by one or more computers, the method includes: identifying a set of tasks for a server system to perform; performing multiple performance testing cycles, where each of the performance testing cycles includes: sending, for each task in the set of tasks, a request for the server system to perform the task; receiving a response from the server system for each of the requests; and storing a performance measure for each of the tasks based on the response received from the server system for the task; and evaluating, based on the performance measures for the multiple performance testing cycles, whether conditions are satisfied for adjusting one or more operating parameters of the server system or for providing a notification regarding the operation of the server system.

Implementations may include one or more of the following features. For example, in some implementations, where the set of tasks includes loading a specific set of multiple documents provided by the server system.

In some implementations, the set of tasks includes loading a particular portion of a document and performing one or more predetermined interactions with the particular portion of the document.

In some implementations, the method includes performing the multiple performance cycles on an ongoing basis while the server system processes user-initiated requests to the server system.

In some implementations, sending the requests for the tasks includes sending requests that simulate user-initiated requests from user devices to the server system.

In some implementations, the performance measure includes determining a completion time or a response time for individual tasks.

In some implementations, the multiple performance testing cycles are managed by a testing server system, where the set of tasks includes rendering a document served by the server system using a browser instance of the testing server system, and where the performance measure for one of the tasks includes an amount of time to complete rendering of the document by the browser instance.

In some implementations, the method further includes initiating one or more browser instances by the one or more computers. In these implementations, sending the requests includes sending the requests from the one or more browser instances.

In some implementations, the method includes performing the performance testing cycles at a predetermined interval. In these implementations, each of the performance testing cycles includes requesting that each document in a predetermined set of documents to be served by the server system, the documents being requested sequentially and in order in a same sequence in each performance testing cycle, the requests being spaced apart during a performance testing cycle such that the each individual document is received from the server system before the subsequent document in the sequence is requested from the server system.

In some implementations, determining the performance measure is based on a time a request is initiated and a time a corresponding response from the server system is received.

In some implementations, the method includes evaluating a progression of performance measures over multiple performance measurement cycles to determine an aggregate performance measure for the server system, where the aggregate performance measure indicates an average performance of the server system over a period of time or a trend or a pattern of change in performance of the server system over a period of time.

In some implementations, the method includes: determining, for each of the tasks in the set of tasks, (i) a load level experienced by the server system at the time the task is performed and (ii) an indication of hardware resources available to the server system at the time the task is performed; determining a relative performance measure for the server system that takes into account the performance measures for the tasks, the load levels when the tasks were performed, and the hardware resources available when the tasks were performed; and comparing the relative performance measure for the server system with relative performance measures of one or more other server systems.

In some implementations, the method includes providing, to one or more devices, an indication of a response time, an average response time, a maximum response time, or a number of errors for the server system.

In some implementations, identifying the tasks includes including, in the set of tasks: one or more tasks that are specified by a user to be included in the set of tasks; one or more tasks determined, based on log data for the server system, to have the highest frequency among user-initiated requests to the server system; or one or more tasks to load documents identified, based on log data for the server system, has being most frequently accessed.

In some implementations, evaluating whether conditions are satisfied includes: accessing a set of rules that indicate different criteria and corresponding actions to perform when the respective criteria are satisfied; determining that a particular one or more criteria is satisfied by the performance measures; and initiating the action corresponding to the particular one or more criteria.

In some implementations, the evaluating includes determining, based on the performance measures obtained during multiple performance cycles, that performance of the server system has declined by at least a minimum amount. In these implementations, the method includes, in response to determining that the performance of the server system has declined by at least the minimum amount, providing a notification to an administrator for the server system and/or initiating a change to one or more operating parameters of the server system.

Other embodiments of these aspects include corresponding systems, apparatus, and computer programs encoded on computer storage devices, configured to perform the actions of the methods. A system of one or more computers can be so configured by virtue of software, firmware, hardware, or a combination of them installed on the system that, in operation, cause the system to perform the actions. One or more computer programs can be so configured by virtue having instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features and advantages of the invention will become apparent from the description, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram that illustrates an example system for monitoring performance of computing systems.

FIGS. 2A-2B are diagrams that illustrates example interfaces displaying performance data.

FIG. 3 is a diagram that illustrates an example system for performing actions based on monitored performance.

FIG. 4 is a diagram that illustrates an example interface displaying performance data.

FIG. 5 is a diagram that illustrates an example interface displaying performance data.

Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

FIG. 1 is a diagram that illustrates an example system 100 for monitoring performance of computer systems. The system 100 includes a management system 110 that performs performance monitoring, a server system 130 to be monitored, client devices 132, and a network 140.

The system 100 can be used to monitor the end-to-end performance and reliability that would be experienced by a user interacting with the server system 130. The management system 110 can automatically and precisely measure the end-to-end response time to perform one or more tasks, such as loading a document provided by a server, by simulating a user initiating the tasks. The management system 110 may monitor the response time on a continual or ongoing basis by repeatedly performing the specified tasks. The management system 110, by repeatedly testing the server system 130 at regular intervals, can establish a detailed view of the performance of the server system 130 over time. This enables the management system 110 to detect and react to performance changes and performance trends for the monitored server system 130, as well as to establish the nature of normal performance patterns of the server system 130.

The management system 110 may organize and display monitored end-user-experience performance data. The management system 110 may analyze the end-user-experience performance data to provide a historical breakdown of the monitored end-user-experience performance. Based on the analysis, the management system 110 may perform one or more actions, such as notifying an administrator of performance changes, adjusting settings to improve performance, changing an assignment of users from one system to another, adjusting an allocation of hardware resources, and so on.

FIG. 1 also illustrates various events, shown as stages (A) to (E), with each representing a step in an example process. Stages (A) to (E) may occur in the illustrated sequence, or in a sequence that is different from the illustrated sequence. For example, some of the stages may occur concurrently.

The management system 110 is configured to monitor the performance of one or more different systems. In the example of FIG. 1, the management system 110 monitors the performance of the server system 130 and can communicate with the server system 130 over the network 140. The management system 110 may include one or more computing devices. The management system 110 has a task list 112 that includes a set of tasks to be tested on the server system 130. The management system also includes a request generation module 114 that creates requests that are sent by a headless browser 116 to the server system 130. After the requests are sent, a performance monitoring module 118 evaluates the performance of the server system 130 for different requests and stores performance data in data storage 120.

The server system 130 can include one or more computing devices. The server system 130 can communicate with the client devices 132 over the network 140, in addition to the management system 110. The server system 130 may be an onsite server, an offsite server, or an environment hosted by a cloud computing platform (e.g., Amazon Web Services (AWS), Microsoft Azure, etc.). The server system 130 may be provided, owned, and/or operated by a third-party with respect to the management system 110.

The client devices 132 may be computing devices, such as a desktop computer, a laptop computer, a cell phone, a smart phone, and/or a tablet device.

The network 140 can include public and/or private networks and can include the Internet.

In the example of FIG. 1, the management system 110 initiates tasks to be performed by the server system 130, which represents a server environment that is in use and responding to requests by various other users, e.g., an “in production” system. By performing tasks on a production environment and by treating those tasks the same as if they were initiated by a user, the disclosed system is able to recreate the actual end-user experience. The disclosed system can monitor the resulting performance data to obtain accurate end-user-experience performance for particular tasks. Additionally, this performance data may be used by an administrator or by the system itself to modify server configuration settings in order to improve performance.

By monitoring performance as discussed below, the management system 110 can quickly identify errors or performance decreases that affect end users of the server system 130. In some implementations, the management system 110 tests each task in the task list 112 sequentially. After all the items in the task list have been tested, the management system 110 repeats the testing of all the items in the task list 112. By repeating the testing of the items so that performance is tested continually, the management system 110 is able to quickly identify deviations from the server system's 130 typical performance. Among other features, the management system 110 can determine when performance decreases occurred, the magnitude or extent that performance has decreased, and the duration that performance decreases last. In addition to the performance data, the management system 110 can obtain telemetry data about the functioning of the server system 130 (e.g., which software modules are running, which hardware resources are allocated, load levels experienced, current settings, etc.), and use the performance data and the telemetry data to identify and fix the causes of performance decreases.

As shown in FIG. 1, at stage (A), the management system 110 obtains a task list 112 that specifies the set of tasks to be tested for the server system 130. As shown, the task list 112 in this example includes the retrieval or generation of specific reports and dashboards. The task list 112 can be generated by the management system 110 and/or a system administrator. In some implementations, a separate task list is determined for each computer system to be monitored. The task list can be representative of the usual workload of the monitored computer system. For example, the task list 112 can be a variety of tasks that represent the most commonly served documents or other most commonly performed functions of the server system 130.

When an administrator generates at least part of the task list 112, the management system 110 can provide a list of tasks that can be performed by the server system 130 and/or associated items, such as documents provided by the server system 130. Examples of tasks include accessing an item, logging in a user, retrieving an item or part of an item, loading an item, rendering an item, filtering an item, scrolling through an item to a particular location, etc. As an example, an administrator's client device may provide a user interface that shows a list documents or other items stored on the server system 130. The items may include, for example, reports, dashboards, documents, websites, etc. In this example, when the administrator selects an item, they may be presented a drop-down menu of available tasks that can be performed with the item. An administrator may then select one or more tasks or operations to be performed with the item. If multiple tasks are selected to be performed with the item, then a workflow specifying the multiple tasks may be created, and the workflow can be added to the task list 112.

In some implementations, the task list 112 is generated in part or entirely by the management system 110. For example, the management system 110 may access usage logs that indicate the tasks that users have initiated over a period of time (e.g., the previous day, week, month, etc.). The management system 110 may then select the tasks most frequently performed by users to the task list 112 and/or select the items that users most frequently interact with. For example, the management system 110 may identify the most frequently accessed resources in different categories (e.g., reports, data cubes, dashboards, etc.). The management system 110 can then select a predetermined number (e.g., 3, 5, 10, etc.) of the most frequently accessed resources in each category, and add the generation of or other access to the selected resources as tasks in the task list 112. Over time, as the usage patterns for the server system 130 change, the management system 110 can also change the set of tasks in the task list 112 to reflect the new usage patterns, e.g., by adding newly popular tasks and removing tasks that have become less popular.

Even when the management system 110 selects some or all of the tasks for the task list 112, a system administrator may modify the tasks or edit the task list 112. An administrator may modify a task list (e.g., the task list 112) generated by the management system 110, for example, by adding available tasks and/or items to the list or removing tasks and/or items from the list.

In some implementations, a task can specify an action regarding a part or subset of an item, such as a location within a document. For example, an administrator may specify that a task involves retrieving only the first three pages of a particular document, rather than retrieving the entire document. Similarly, the management system 110 may also define tasks that represent specific interactions or portions of items, for example, to test performance for a specific part of an item that is frequently accessed.

The items in the task list 112 are arranged in a particular order, which indicates the order in which the tasks are to be tested. The management system 110 may select the order of the tasks in the task list 112. An administrator may select the order of the tasks in the task list 112 or may modify an order selected by the monitoring system 100. Here, the task list 112 includes the generation of the first report 124 (“Report 1”), the second report 128 (“Report 2”), the third report (“Report 3), the first dashboard (“Dashboard 1”), and the second dashboard (“Dashboard 2”), in the recited order.

In general, the tasks in the task list 112 can be set to be performed sequentially. For example, the management system 110 initiates testing for the first task and waits to initiate the second task until the first task is completed. This can help limit the impact of performance monitoring on other concurrently running tasks, and can improve the reliability of testing. In some implementations, one or more tasks in the task list 112 are designated to be tested concurrently instead of sequentially. Concurrent testing of two or more tasks may have been specified during generation of or editing of the task list 112. For example, an administrator may select two reports and indicate that they should be tested concurrently. In this example, an administrator may select these two reports for concurrent testing or the management system 110 may suggest these two reports to the administrator for concurrent testing if it is known that users frequently use these reports together or contemporaneously with one another.

At stage (B), the management system 110 launches an application, such as the browser 116, and the request generation module 114 generates requests for the application to send to the server system 130. The application can be a web browser or other application that communicates with a server system. The browser 116 may be a headless browser, for example, a browser that does not have any corresponding display. The browser 116 receives requests generated by the request generation module 114 and sends the requests to the server system 130. In some implementations, the request generation module 114 sends the generated requests to the browser 116 sequentially in the order specified in the task list 112.

In the example of FIG. 1, the browser 116 is used to send requests to and receive responses from the server system 130, in a manner that the requests are perceived to be user traffic by the server system 130. The management system 110 can concurrently run various other browser instances to communicate with other server systems being monitored by the management system 110. Similarly, the request generation module 114 can generate requests for multiple server environments, based on the same or different task lists.

The request generation module 114 accesses the task list 112 and generates a request for each of the tasks in the task list 112. Accordingly, the request generation module 114 generates the first request 122 a for the first report 124 (“Report 1”), the second request 126 for the second report 128 (“Report 2”), the third request for the third report (“Report 3), the fourth request for the first dashboard (“Dashboard 1”), and the fifth request for the second dashboard (“Dashboard 2”).

In some implementations, when the request generation module 114 has finished generating requests for each of the tasks in the task list 112, it will repeat the process, starting with generating the new request 122 b for the first report 124. Alternatively, the request generation module 114 may reuse the previously generated requests (e.g., request 122 a is the same as request 122 b).

The request generation module 114 generates the requests in such a way so as to simulate a request made by a typical user. Accordingly, the requests created by the request generation module 114 may be absent of any special permissions or authorizations, may use a standard pathway (e.g., the same server sockets that users typically use), may be placed in a standard queue, etc. As an example, the generated requests may appear the same or similar to requests originating with the client devices 132.

The generated requests may contain an indication of the task to be performed and/or an indication of any associated items. For example, the generated requests may include an address of an item's location on the server system 130, such as a URL for the item. For example, the generated requests may include the name or other identifier of an item associated with a task (e.g., Report 1). For example, the generated requests may include an identifier for a location within an item associated with a task such as a page number (e.g., page 2 of Report 1). For example, the generated requests may include credentials for particular tasks such as logging in. For example, the generated requests may include a name or other identifier for the task to be performed (e.g., access, load, retrieve, generate, etc.).

At stage (C), the browser 116 sends the generated requests to the server system 130 over the network 140 and receives responses from the server system 130 over the network 140. Here, the management server 110 sends the first request 122 a for the first report 124 (“Report 1”), the second request 126 for the second report 128 (“Report 2”), the third request for the third report (“Report 3), the fourth request for the first dashboard (“Dashboard 1”), and the fifth request for the second dashboard (“Dashboard 2”) to the server system 130. The browser 116 sends the requests, including the requests 122 a and 126, in a manner instructed by the request generation module 114, which can be sequentially in the order specified in the task list 112. The browser 116 may send one or more of the requests concurrently.

After the management server 110 sends a request to the server system 130, the management server 110 receives a response from the server system 130. Here, the management server 110 receives the first report 124 as a response to the request 122 a, and receives the second report 128 as a response to the request 126.

The management system 110 records a time at which each of the requests is sent and a time at which each of the corresponding responses is received. In some implementations, the browser 116 waits to receive a response (e.g., fulfillment of a request) before sending the next request. For example, the browser 116 may wait to receive the report 124 requested by request 122 a before sending the request 126. This can facilitate the performance of sequences of operations involving the same resources. For example, one task may retrieve a document, the next task may perform an operation on a part of the document, the next task may save a copy of the document, and so on. Performing the tasks in sequence can ensure that the appropriate data or state is available when each task is initiated, and the process can appropriately simulate typical user behavior.

In some implementations, for example when running independent tasks, the browser 116 does not wait to receive a response to a request before sending the next request. For example, the browser 116 may send the request 126 before receiving the report 124.

In some implementations, the browser 116 sends one or more requests concurrently. For example, the browser 116 may send the requests 122 a and 126 at the same time or approximately the same time.

After the management system 110 has finished sending a request for each of the tasks in the task list 112 (and, in some implementations, has received each of the corresponding responses), the management system 110 repeats the process. As shown, after sending requests for each task in the task list 112, the browser 116 sends the new request 122 b to obtain the report 124 again. The management system 110 causes the browser 116 to then continue cycling through the tasks in the task list 112, recording the performance of the server system's 130 execution of the tasks each time.

Where the response includes an item such as a document, the browser 116 may perform additional actions on the item based on the corresponding task. For example, the browser 116 may load or render the reports 124 and 128 that are received from the server system 130. The browser 116 may perform the steps of a workflow with the retrieved item. The steps of the workflow may be based on steps that are typically performed by users with the particular retrieved item. For example, the browser 116 may open the report 124, scroll to page 2 of the report, and filter the report by geography. This sequence of actions may be derived from usage logs that indicate, for example, that 60% of users perform these steps with the report 124. The management system 110 may record the time it takes to perform each of these additional actions. The management system 110 may determine these times using the browser 116. For example, in addition to recording the time at which request 122 a was sent and the time at which the report 124 was received, the browser 116 may render the report 124 and record the time at which the report 124 rendering was completed.

At stage (D), the management system 110 provides the recorded times to the performance monitoring module 118. The performance monitoring module 118 may use the recorded times to calculate current performance metrics. These current performance metrics may include a response time, a task completion time (which may, in some instances, be equivalent to the response time), an individual action time (e.g., time to load an item or part of an item, time to render an item or part of an item, time to scroll through an item, time to filter an item, etc.).

The performance monitoring module 118 may compare the time at which the request 122 a was sent from browser 116 with the time at which report 124 was received by the browser 116 in order to calculate a first response time for request 122 a. The performance monitoring module 118 may compare the time at which the request 122 a was sent from the browser 116 with the time at which the report 124 was rendered in order to calculate a first task completion time for the report 124. The performance monitoring module 118 may compare the time at which the report 124 was received by the browser 116 with the time at which the report 124 was rendered in order to calculate a first rendering time for the report 124.

The performance monitoring module may analyze the calculated performance metrics. The performance monitoring module 118 may issue an error or a warning based on one or more of the performance metrics. An error or warning may occur if a performance metric is unusually high, unusually low, or cannot be calculated.

The performance metrics determined by the management system 110 can be used to establish a baseline level of performance for the server system 130, which can be expressed as thresholds that represent average response time, maximum response time, and so on. The management system 110 can determine that performance deviation has occurred when a metric does not satisfy one of the thresholds representing typical performance. These thresholds can be predetermined or variable. In general, the performance monitoring module 118 may determine thresholds for different performance metrics as an average of that performance metric over multiple cycles of testing, e.g., multiple iterations of the tasks in the task list 112. The threshold can be based on a moving average that covers results from a most recently time period.

For example, the performance monitoring module 118 calculates a 2-day average task completion time for generating the report 124. The performance monitoring module 118 may use a timestamp for sending the request 122 a and a timestamp for receiving the report 124 to determine a task completion time. The performance monitoring module 118 may then compare the current completion time with the average completion time to determine whether the difference exceeds some magnitude, such as taking at least 25% longer than the average. When the result is determined to take at least 25% longer than average, the performance monitoring module may issue a warning. Various warnings and other actions can be taken for different levels of performance deviations. For example, if the result is 200% slower than the average, a higher priority notification may be issued, or a corrective action may be initiated.

In addition, performance thresholds can be selected by an administrator. For example, an administrator may specify that if a response time is greater than 5 seconds for any report, then the administrator should be notified.

An unusually low performance metric is associated with a time that is shorter than expected. A short time may indicate that a task was not fully performed. The performance monitoring module 118 may determine that a performance metric is unusually high if it is above a threshold (e.g., a predetermined or variable threshold) as, for example, selected by an administrator.

If a performance metric cannot be calculated, this may indicate that there was a failure in performing the task. For example, a performance metric might not be calculated if an item was unable to be rendered, an item was never received from the server system 130, an invalid response was received from the server system 130, etc.

If an error or warning is determined, the management system 110 may perform one or more actions. For example, the management system 110 may generate and send a notification or other alert to a system administrator. The notification may include an indication of performance changes that have been detected by the management system 110 and which have resulted in the error or warning. As another example, the management system 110 may adjust server configuration settings of a particular server system to improve the performance of that server system. Adjusting server configuration settings may include, for example, modifying the network bandwidth of the server system 130, the latency of the server system 130, the cache size of the server system 130, the working data amount for operations performed by the server system 130, and/or the version of software used by the server system 130. As another example, the management system 110 may adjust an allocation of hardware resources for a particular server system to improve the performance of that server system. Adjusting the allocation of hardware resources may include, for example, modifying the number of CPUs allocated to the server system 130, and/or the amount of memory (e.g., RAM) allocated to the server system 130. As another example, the management system 110 may change an assignment of users from one server system, such as the server system 130, to one or more different server systems. By reducing the number of users on one server system, such as the server system 130, the management system 110 can improve the performance of that server system.

At stage (E), the performance monitoring module 118 stores the calculated performance metrics in the data storage 120. There may be stored performance metrics for a task list (e.g., the task list 112), for an individual task (e.g., the report 124), and/or for a component of a task (e.g., individual pages of documents or reports, individual elements of pages, etc.). There may be multiple stored performance metrics for each task list, for each task, and/or for each component of a task. For example, the data storage 120 may contain five performance metrics for rendering page three of the report 124. In this example, the five performance metrics may be rendering times for the five most recent renderings of page three of the report 124. The stored performance metrics may be tagged with a time and date. The performance metrics may be organized in the data storage 120 by the order in which the task list, the tasks, and/or the components of a task were performed. For example, the performance metrics of the task list 112, of the individual tasks within the task list 112, and/or the components of the tasks within the task list 112 may be stored in the data storage 120 in the task order of the task list 112.

At stage (F), the performance monitoring module 118 accesses the data storage 120 to obtain previously calculated performance metrics for a particular task and/or item and analyzes the previously calculated performance metrics. Based on the analysis, the performance monitoring module 118 may calculate historical performance metrics for the particular task and/or item. Historical performance metrics may include, for example, average response time over a specified period (e.g., 1 hour, 12 hours, 1 day, 2 days, 1 week, 10 days, 2 weeks, 20 days, 1 month, etc.), an average task completion time for a particular task and/or item over a specified period, an average action time for a particular item over a specified period, an average success rate (e.g., the rate at which performing a task with a particular item does not result in an error and/or a warning), a maximum rate (e.g., the longest amount of time it has taken to perform a task with a particular item), a number of times a task has been performed or performed with a particular item (e.g., the number of times a particular item has been generated for monitoring purposes), a total number of warnings associated with a particular task and/or item, a total number of errors associated with a particular task and/or item, etc.

The performance monitoring module 118 may issue an error or a warning based on one or more of the historical performance metrics. An error or warning may occur if a historical performance metric is unusually high or unusually low with respect to thresholds representing desired levels, or if the performance metric cannot be calculated. Determining that a historical performance metric is unusually high or low may involve comparing the historical performance metric with one or more thresholds. For example, there may be a high error threshold, a high warning threshold lower than the high error threshold, a low error threshold, and a low warning threshold higher than the low error threshold. The performance monitoring module 118 may store the calculated historical performance metrics in the data storage 120 as part of the performance data.

The management system 110 may determine a relative performance measure, such as a relative performance index (RPI), for the configuration settings of the server system 130. The RPI value indicates the level of performance when a particular combination of configuration settings is used, after the influence of the hardware resources and/or the load levels of a particular server environment have been removed or reduced.

In order to remove the influences and determine the RPI, the management system 110 may normalize the performance results (e.g., the performance metrics calculated by the performance monitoring module 118 and/or the performance metrics stored in the data storage 120) for the hardware resources used by the server system 130 during the testing process, and/or normalize the load levels on the server system 130 during the testing process. In order to normalize the performance results and/or the load levels, the management system 110 may first obtain telemetry data about the functioning of the server system 130. The telemetry data may include an indication of which software modules are running on the server system 130, which hardware resources are allocated to the server system 130, load levels experienced by the server system 130 (e.g., total load including the traffic from the client devices), the current server configuration settings for the server system 130, etc.

Normalizing the performance results may involve scaling the performance results based on differences in load level and/or differences in hardware resources as indicated by the obtained telemetry data of the server system 130. This process can boost or penalize performance metrics to estimate how the server system 130 would have performed if it had the same hardware resources available and experienced the same load levels as one or more other server systems, or as a standard or model server system. As a very simple example, the performance metrics could be normalized to the equivalent of a 50% load level. For a task that scales linearly with load capacity, the scaling factor could be 1+(50−X)/100, where “X” represents the load level percentage. As a result, if the server system 130 had a load level of 80% at the time of testing, a 1.0 second task completion time may be scaled from 1.0 seconds to 1.0*(1−30/100)=0.7 seconds. Similarly, a different server system that had a load level of 30% at the time of testing and also achieved a 1.0 second task completion time may be scaled from 1.0 seconds to 1.0*(1+20/100)=1.2 seconds. Differing hardware capabilities can also be taken into account with scaling factors. The scaling used during the normalization of the performance metrics may be linear or non-linear. In some implementations, the scaling or the RPI score itself is determined by a machine-learning model that has learned from examples, previous performance results, and/or previous configuration settings.

In some implementations, the RPI is determined for overall performance. That is, the RPI might account for each type of performance metric. For example, the RPI might account for the response time(s), the task completion time(s), the concurrency, the frequency of errors, the type of errors, and the accuracy of results. However, each of these performance aspects are not necessarily weighted the same when determining the RPI. In some implementations, multiple RPI scores may be calculated for different types of performance metrics, e.g., with one RPI score being a normalized indication of response time, another RPI score representing a normalized indication of accuracy, etc.

In actual implementations, the techniques for normalizing the performance metrics and generating RPI values can be defined or learned empirically. Different tasks or portions of tasks are sensitive to different factors, e.g., memory size, memory latency, CPU speed, number of concurrent tasks, and so on, and there may be non-linear or unpredictable relationships of these factors on performance. The management system 110 can run the tasks used for testing in different, controlled conditions to characterize the effects of different hardware changes and load levels on performance. This can enable the management system 110 to characterize how different conditions affect performance. In other words, the management server 110 can operate a server environment and with the same software configuration settings, run a suite of tests with the environment experiencing 0% load, then 5% load, then 10% load, then 15% load and so on. Similarly, the management system 110 can operate a server environment with the same software configuration settings and different hardware resources, e.g., different numbers of processors, different types of processors, different memory sizes, and so on. By testing different combinations of load levels and hardware resources while keeping software settings and other factors constant, the management system 110 can isolate the effects of (and interplay of) load level and hardware resources, to develop the data points that show how change in load and hardware affect performance. Of course, the characterization of effects of load and hardware on performance can be done for each of various different combinations of configuration settings, so that the particularities of one combination of configuration settings do not skew the relationships that will be used for normalizing results. With the load/hardware characterization data points, the management system 110 can extract the relationships needed to normalize for changes in load and hardware. This can be done thorough any appropriate technique, such as regression modelling, curve fitting, or machine learning.

As an example, the management system 110 can use the data points that characterize the performance of a single software configuration over different load and hardware conditions to train machine learning models. For example, a machine learning model can be trained to receive input indicating actual performance measured for a test, load statistics during the test, and hardware used by the tested environment, and output an RPI. The parameters of the machine learning model can be trained so that substantially the same RPI is produced for a single test and software configuration, even for different absolute performance results achieved due to different load and hardware conditions. By training models in this way, the models can learn the complex interaction between different types of tasks with load levels and hardware resource availability, and perform a normalization that takes them into account.

In some implementations, the requests 122 a, 126, and 122 b may be sent by a mobile computing device. For example, the requests 122 a, 126, and 122 b may be sent by a smart phone, a tablet computer, a laptop computer, etc. The mobile computing device may be a mobile computing device of an administrator of the management system 110. The mobile computing device may be a mobile computing device of a user of the management system 110. The mobile computing device may be able to communicate with the management system 110. As an example, the mobile computing device may receive the task list 112 from the management system 110. The mobile computing device may generate requests for each of the tasks within the task list 112. The mobile computing device may then send each of the generated requests to the server system 130. The mobile computing device may send a sent time for each of the requests 122 a, 124, and 122 b to the management system 110.

In some implementations, responses from the server system 130 may be received by a mobile computing device. For example, the first report 124 and the second report 128 may be received by a smart phone, a tablet computer, a laptop computer, etc. The mobile computing device may be a mobile computing device of an administrator of the management system 110. The mobile computing device may be a mobile computing device of a user of the management system 110. The mobile computing device may be able to communicate with the management system 110. In these implementations, the mobile computing device may have sent the requests 122 a, 124, and 122 b to the server system 130. As an example, the mobile computing device may receive the first report 124 and the second report 128 from the server system 130. The mobile computing device may then record various times associated with the first report 124 and the second report 128, e.g., a time when each report was received, a time when each report was rendered, etc. The mobile computing device may then send these times to the management system 110 or may calculate performance metrics associated with the first report 124 and/or the second report 128 itself, e.g., where the mobile computing device sent the requests 122 a, 124, and/or 122 b to the server system 130.

FIGS. 2A-2B are diagrams that illustrates example interfaces displaying performance data.

As shown in FIG. 2A, an interface 200 a displays performance data. The performance data may be organized by date such that there is a window for each day or other specified time period (e.g., 12 hours, 2 days, 1 week, 10 days, 20 days, 1 month, etc.). Here, a window 202, for the date of Mar. 11, 2019, includes a list of various tasks 204, a list of monitored request times 206 for each of the tasks, a list of monitored response times 208 for each of the tasks, a list of rendering times 210 for each of the tasks, and a list of total times 212 for each of the tasks (i.e., amount of time needed to perform the task). The total times 212 may represent a current performance metrics as calculated, for example, by the performance monitoring module 118 of the management system 110 as shown in FIG. 1. The values included in the list of the total times 212 may be in seconds.

The tasks 208 include the same tasks in the task list 112 as shown in FIG. 1. Here, the name of each of the items (e.g., “Report 1”) in the tasks 204 is associated with the task of generating that item.

Here, as indicated by the request times 206 and the rendered times 210, a request for a following task of the tasks 204 is not sent until the previous task of the tasks 204 is complete (e.g., until the associated item has been rendered). The request for the following task of the tasks 204 may be sent immediately following the completion of the previous task of tasks 204.

As discussed with reference to FIG. 1, the set of tasks may be repeatedly performed in a continual or repetitive manner. Accordingly, after the last task of a set is performed (e.g., the last task of the task list 112 as shown in FIG. 1), the first task of the set is performed again. For these reasons, Report 1 appears a second time in the tasks 204 immediately following the rendering of Dashboard 1.

As shown, despite Report 1 being generated twice in a short span of time, two different response times, found in the total times 212, are monitored. The first time of 1.32 is slower than the second time of 1.21, indicating an improvement in task performance.

Further scrolling through the window 202 may reveal additional performance data for the various tasks. The additional performance data may reveal additional request times of the request times 206, additional response times of the response times 208, additional rendering times of the rendering times 210, and additional total times of the total times 212 for generating the Report 1, the Report 2, the Report 3, the Dashboard 1, and the Dashboard 2. The additional performance data may reveal that repeated generation of the Report 1, the Report 2, the Report 3, the Dashboard 1, and the Dashboard 2 consistently and constantly throughout Mar. 11, 2019 in the stated order.

As shown in FIG. 2B, an interface 200 b displays historical performance data. The interface 200 b includes a window 220 containing a list of items 222, a list of tasks 224 performed with the items 222, a list of time values 226 representing averages over the past two days, a list of time values 228 representing averages over the past twenty days, and a list of percentages 230 representing the percent change between the time values 228 and the time values 226. The time values 226 and 228 may represent values in seconds. A positive percentage of the percentages 230 is associated with an improvement in task performance, whereas a negative percentage of the percentages 230 is associated with a decline in task performance.

Although the time values 226 represent averages over the past two days, other time ranges may be selected and displayed. For example, a time range of the past six hours, the past 12 hours, the past day, the past three days, or the past week may be selected and displayed in the window 220.

Although the time values 228 represent averages over the past 20 days, other time ranges may be selected and displayed. For example, a time range of the past week, the past 10 days, the past 14 days, the past month or 30 days, the past six months, or the past year may be selected and displayed in the window 220.

The items found in the items list 222 include Report 1 and Report 2. Further scrolling through the window 220 may reveal additional items. These additional items may include the other reports and the dashboards found in the task list 112 as shown in FIG. 1.

The task list 224 includes the tasks of generating an item, and generating and applying a filter to an item. Further scrolling through the window 220 may reveal additional tasks. These additional tasks may include, for example, accessing an item, logging into one or more systems, retrieving an item, loading an item or part of an item, rendering an item or part of an item, scrolling through an item, etc.

FIG. 3 is a diagram that illustrate a system 300 for performing actions based on monitored performance. The system 300 includes the management system 110, the server system 130, and an administrator device 312. The management system 110 includes the performance monitoring module 118 and the data storage 120 containing performance data.

While analyzing current performance data or analyzing historical performance data, the performance monitoring module 118 may detect a deviation in task completion times (302). This deviation may be associated with a warning or an error as discussed above with reference to FIG. 1. If a warning or an error is determined to be associated with the detected deviation, the performance monitoring module 118 may store the warning or the error as part of the performance data in data storage 120.

Based on the detected deviation, the management system 110 determines one or more actions to perform (304). These actions may include, for example, notifying an administrator of performance changes, adjusting settings to improve performance, changing an assignment of users from one system to another, adjusting an allocation of hardware resources, and so on. The administrator may be an administrator of the server system 130. Determining the one or more actions to perform may be based on whether the deviation is associated with a warning or with an error. For example, if the performance data meets a first threshold but does not meet a second threshold, the management system 110 shown in FIG. 1 may determine that the deviation should be classified as a warning and may send a corresponding notification to an administrator. As another example, if the performance data meets both a first threshold and a second threshold, the management system 110 may determine that the deviation should be classified as an error and may send a higher priority notification to the administrator and may perform additional actions such as adjusting the configuration settings of the server system 130 shown in FIG. 1. The thresholds may be based on a baseline level of performance established by the management system 110 for the server system 130. For example, the first threshold may be 50% above the baseline and the second threshold may be 200% above the baseline. The thresholds may be automatically calculated using the established baseline. The thresholds may be set by a system administrator. The thresholds may be set by a machine learning network.

The management system 110 may determine to select new server configuration settings and send instructions to the server system 130 (306). This action may be selected by the management system 110 where deviations in task completion times indicate poor performance but not necessarily an error. For example, if it is determined that the generation of reports on the server system 130 takes on average 20% longer than recommended, the management system 110 may select new configuration settings for the server system 130 such that 20% more RAM is allocated to such tasks. Poor performance or performance that is worse than expected may be associated with a warning. The configuration settings may include one or more of a network bandwidth, a latency, a cache size, a number of CPUs allocated, a working data amount for operations performed, an amount of memory (e.g., RAM), and/or a version of software used. Upon determining new configuration settings for the server system 130, the management system 110 either sends them to the server system 130 to be immediately applied or sends them to the administrator device 312 for verification.

The management system 110 may determine to select one or more tasks and initiate performance of the selected one or more tasks (308). This action may be selected by the management system 110 where deviations in task completion times indicate a warning or an error. The selected one or more tasks may be those tasks that have been previously associated with a warning or an error. The selected one or more tasks may be those tasks that have been most frequently associated with a warning or an error. The selected one or more tasks may be associated with one or more particular items, such as reports, other documents, dashboards, etc. The management system 110 may initiate performance of the selected one or more tasks by generating a request (e.g., by the request generation module 114 as shown in FIG. 1) and sending the generated request to the server system 130.

The management system 110 may generate a notification and send the generated notification to an administrator (310). The notification may be generated by the performance monitoring module 118. The notification may include the name or other identifier of the task associated with the detected deviation. The notification may include the name or other identifier of an item associated with the task that is associated with the detected deviation. The notification may include an indication of whether a warning or an error was associated with the detected deviation. In sending the generated notification to an administrator, the management system 110 sends the generated notification to the administrator device 312.

FIG. 4 is a diagram that illustrates an interface 400 displaying a detailed view of performance data, including calculated performance metrics. The interface 400 includes a table 402. The table 402 provides a detailed view of the task of generating all pages of Report 1. The calculated performance metrics include calculated performance metrics for each page of an example Report 1 (e.g., the first report 124 as shown in FIG. 1). The performance metrics include a last generation performance time for each page in seconds, a maximum time for each page in seconds, the number of tests of each page, and a total number of errors experienced during the generation of each page.

Each of the pages a report may be provided a name. The pages names may be user-definable. As shown, a third page of Report 1 is named “Status Panel”, a fourth page of Report 1 is named “Organization”, a fifth page of Report 1 is named “Product”, a sixth page of Report 1 is named “Current Period”, a seventh page of Report 1 is also named “Product”, an eighth page of Report 1 is named “Current Iteration”, and a ninth page of Report 1 is named “Planning Readiness.” As an example, with respect to FIG. 1, a user of the server system 130 may be able to provide the names for each of the pages in the first report 124 through one of the client devices 132.

The performance metrics are also organized by the server from which Report 1 and/or the pages of Report 1 are requested. As shown, performance metrics are provided for a first server 406 (“Server 1”) and a second server 408 (“Server 2”).

If a performance metric is determined to be associated with a warning or an error (e.g., by the performance monitoring module 118 as shown in FIGS. 1 and 3), then the performance metric may be distinguished from other performance metrics. For example, if a performance metric is determined to be below a warning threshold but above an error threshold, it may be presented with a warning color (e.g., yellow) or shade that is different from a healthy color (e.g., green) or shade (or absence of shade) and different from an error color (e.g., red) or shade.

As shown, healthy performance metrics are left unshaded, performance metrics indicating a warning are marked with a first shade, and performance metrics indicating that an error has likely occurred are marked with a second shade that is darker than the first shade. Here, a warning threshold for a maximum generation time may be 5.00 seconds, and an error threshold for a maximum generation time may be 10.00 seconds. In addition, a warning threshold for a minimum reliability may be 99.00%. Because generation of page 6 of Report 1 requested from Server 1 took 5.38 seconds, the performance metric met the warning threshold but not the error threshold. As such, the performance metric of a 5.38 second time indicates a warning. Similarly, because generation of page 5 of Report 1 requested from Server 1 took 12.14 seconds, the performance metric met the error threshold. As such, the performance metric of a 12.14 second time indicates that an error has likely occurred. The detection of an error may trigger a higher priority action than the detection of a warning.

The interface 400 also includes a graph 404 depicting the time in seconds to execute all pages of Report 1 over time. The graph 404 is a line graph with three different data sets. The graph 404 includes a first data set representing the performance associated with the first server 406 for the generation of all pages of Report 1. The graph 404 includes a second data set representing the performance associated with the second server 408 for the generation of all pages of Report 1. The graph 404 includes a third data set for the performance associated with a third server 410 for the generation of all pages of Report 1.

In some implementations, the interface 400 multiple graphs instead of the single graph 404. For example, the interface 400 may include a graph for each of the data sets. Specifically, the interface 400 may include separates graphs, each graph representing data from either the first server 406, the second server 408, or the third server 410.

With respect to FIG. 3, the interface 400 may be presented on an administrator device 312. The interface 400 may be generated based on data included in a notification sent by the management system 110 to the administrator device 312. In some cases, the interface 400 may presented on one or more other devices. For example, the interface 400 may be presented on one or more of the client devices 132 as shown in FIG. 1.

FIG. 5 is a diagram that illustrates an interface 500 displaying a simplified view of performance data, including some calculated performance metrics. The interface 500 is broken up into three columns, one for each of the servers to which requests were made. There is a first column 502 a for an example Server 1 (e.g., the first server 406 as shown in FIG. 4). There is a second column 502 b for an example Server 2 (e.g., the second server 408 as shown in FIG. 4). There is a third column 502 c for an example Server 3 (e.g., the third server 408 as shown in FIG. 4). Each of the columns includes performance metrics for a particular task.

Each column of columns 502 a-502 c includes an interface element 504 for the task of generating Report 1. Each column of columns 502 a-502 c includes an interface element 506 for the task of generating Report 2. Each column of columns 502 a-502 c includes an interface element 508 for the task of generating Report 3. Each column of columns 502 a-c includes an interface element 510 for the task of generating Dashboard 1.

Each of the interface elements 504 a-504 c includes performance metrics relating to the task of generating Report 1. Each of the interface elements 506 a-506 c includes performance metrics relating to the task of generating Report 2. Each of the interface elements 508 a-508 c includes performance metrics relating to the task of generating Report 3. Each of the interface elements 510 a-510 c includes performance metrics relating to the task of generating Dashboard 1. These performance metrics include a last time, an time for the generation immediately preceding the last generation, a percent change between the two times, and a graph depicting the task time on the particular server over time. A positive percent change in time indicates decreased performance and may be shown in a first color (e.g., red) or shade different from a negative percent change. A negative percent change in time indicates increased performance and may be shown in a second color (e.g., green) or shade (or absence of shade) different from a positive percent change.

A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. For example, various forms of the flows shown above may be used, with steps re-ordered, added, or removed.

Embodiments of the invention and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the invention can be implemented as one or more computer program products, e.g., one or more modules of computer program instructions encoded on a computer readable medium for execution by, or to control the operation of, data processing apparatus. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter effecting a machine-readable propagated signal, or a combination of one or more of them. The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal that is generated to encode information for transmission to suitable receiver apparatus.

A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for performing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Moreover, a computer can be embedded in another device, e.g., a tablet computer, a mobile telephone, a personal digital assistant (PDA), a mobile audio player, a Global Positioning System (GPS) receiver, to name just a few. Computer readable media suitable for storing computer program instructions and data include all forms of non volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

To provide for interaction with a user, embodiments of the invention can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.

Embodiments of the invention can be implemented in a computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the invention, or any combination of one or more such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.

The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.

While this specification contains many specifics, these should not be construed as limitations on the scope of the invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments of the invention. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

In each instance where an HTML file is mentioned, other file types or formats may be substituted. For instance, an HTML file may be replaced by an XML, JSON, plain text, or other types of files. Moreover, where a table or hash table is mentioned, other data structures (such as spreadsheets, relational databases, or structured files) may be used.

Particular embodiments of the invention have been described. Other embodiments are within the scope of the following claims. For example, the steps recited in the claims can be performed in a different order and still achieve desirable results. 

What is claimed is:
 1. (canceled)
 2. A method performed by one or more computers, the method comprising: accessing, by the one or more computers, usage data indicating previous requests sent to a server system from remote client devices over a communication network; based on the usage data indicating previous requests sent to the server system, generating, by the one or more computers, a set of tasks to be performed by the server system during each of a series of testing cycles, wherein the tasks in the set of tasks are determined based at least in part on frequencies that the usage data indicates different documents or different types of tasks were requested by the remote client devices; in each testing cycle of the series of testing cycles, (i) sending, by the one or more computers, test requests to the server system that simulate requests from remote client devices to perform the tasks in the set of tasks, and (ii) receiving, by the one or more computers, responses that the server system provides in response to the test requests; based on the received responses from the server system, determining, by the one or more computers, a set of performance measures for each of the testing cycles in the series of testing cycles, wherein each set of performance measures includes a performance measure for each task in the set of tasks; and comparing, by the one or more computers, the sets of performance measures for the tasks in the set of tasks with reference values for the server system to detect changes in performance of the server system.
 3. The method of claim 2, further comprising determining, for each of the tasks in the set of tasks, a baseline level of performance of the server system for the task based on performance of the server system for each of multiple previous instances of the server system performing the task; wherein comparing the sets of performance measures with the reference values comprises comparing, for each of the sets of performance measures, the performance measure for each task with the corresponding baseline level of performance for the task.
 4. The method of claim 2, wherein comparing the sets of performance measures with reference values for the server system comprises: for each of the sets of performance measures, comparing the performance measure for each task in the set of tasks with a corresponding moving average of performance measures of the server system for the task, the moving average being updated to provide different reference values for the task to be used for evaluating performance measures from at least some of the testing cycles.
 5. The method of claim 2, further comprising: based on the comparison, detecting, by the one or more computers, that performance of the server system for a particular task in the set of tasks deviates from a baseline level of performance for the particular task.
 6. The method of claim 5, further comprising, in response to detecting that performance of the server system for the particular task in the set of tasks deviates from the baseline level of performance for the particular task, changing one or more operating parameters of the server system.
 7. The method of claim 2, further comprising using one or more of the sets of performance measures of the sets of performance measures to update the reference values for the tasks in the set of tasks.
 8. The method of claim 2, wherein sending the test requests to the server system that simulate requests from remote client devices comprises: running a headless web browser; and sending the test requests to the server system from the headless web browser.
 9. The method of claim 2, wherein the usage data comprises usage logs that indicate past interactions between the server system and the remote client devices.
 10. The method of claim 2, wherein the testing cycles are repeated at a regular interval over a period of time, with the set of performance measures from each of the testing cycles being compared with reference values to detect whether performance decreases below a reference level represented by the reference values.
 11. A system comprising: one or more computers; and one or more computer-readable media storing instructions that, when executed, cause the one or more computers to perform operations comprising: accessing, by the one or more computers, usage data indicating previous requests sent to a server system from remote client devices over a communication network; based on the usage data indicating previous requests sent to the server system, generating, by the one or more computers, a set of tasks to be performed by the server system during each of a series of testing cycles, wherein the tasks in the set of tasks are determined based at least in part on frequencies that the usage data indicates different documents or different types of tasks were requested by the remote client devices; in each testing cycle of the series of testing cycles, (i) sending, by the one or more computers, test requests to the server system that simulate requests from remote client devices to perform the tasks in the set of tasks, and (ii) receiving, by the one or more computers, responses that the server system provides in response to the test requests; based on the received responses from the server system, determining, by the one or more computers, a set of performance measures for each of the testing cycles in the series of testing cycles, wherein each set of performance measures includes a performance measure for each task in the set of tasks; and comparing, by the one or more computers, the sets of performance measures for the tasks in the set of tasks with reference values for the server system to detect changes in performance of the server system.
 12. The system of claim 11, the operations further comprising determining, for each of the tasks in the set of tasks, a baseline level of performance of the server system for the task based on performance of the server system for each of multiple previous instances of the server system performing the task; wherein comparing the sets of performance measures with the reference values comprises comparing, for each of the sets of performance measures, the performance measure for each task with the corresponding baseline level of performance for the task.
 13. The system of claim 11, wherein comparing the sets of performance measures with reference values for the server system comprises: for each of the sets of performance measures, comparing the performance measure for each task in the set of tasks with a corresponding moving average of performance measures of the server system for the task, the moving average being updated to provide different reference values for the task to be used for evaluating performance measures from at least some of the testing cycles.
 14. The system of claim 11, the operations further comprising: based on the comparison, detecting, by the one or more computers, that performance of the server system for a particular task in the set of tasks deviates from a baseline level of performance for the particular task.
 15. The system of claim 14, the operations further comprising, in response to detecting that performance of the server system for the particular task in the set of tasks deviates from the baseline level of performance for the particular task, changing one or more operating parameters of the server system.
 16. The system of claim 11, the operations further comprising using one or more of the sets of performance measures of the sets of performance measures to update the reference values for the tasks in the set of tasks.
 17. The system of claim 11, wherein sending the test requests to the server system that simulate requests from remote client devices comprises: running a headless web browser; and sending the test requests to the server system from the headless web browser.
 18. The system of claim 11, wherein the usage data comprises usage logs that indicate past interactions between the server system and the remote client devices.
 19. The system of claim 11, wherein the testing cycles are repeated at a regular interval over a period of time, with the set of performance measures from each of the testing cycles being compared with reference values to detect whether performance decreases below a reference level represented by the reference values.
 20. One or more non-transitory computer-readable media storing instructions that, when executed by one or more computers, cause the one or more computers to perform operations comprising: accessing, by the one or more computers, usage data indicating previous requests sent to a server system from remote client devices over a communication network; based on the usage data indicating previous requests sent to the server system, generating, by the one or more computers, a set of tasks to be performed by the server system during each of a series of testing cycles, wherein the tasks in the set of tasks are determined based at least in part on frequencies that the usage data indicates different documents or different types of tasks were requested by the remote client devices; in each testing cycle of the series of testing cycles, (i) sending, by the one or more computers, test requests to the server system that simulate requests from remote client devices to perform the tasks in the set of tasks, and (ii) receiving, by the one or more computers, responses that the server system provides in response to the test requests; based on the received responses from the server system, determining, by the one or more computers, a set of performance measures for each of the testing cycles in the series of testing cycles, wherein each set of performance measures includes a performance measure for each task in the set of tasks; and comparing, by the one or more computers, the sets of performance measures for the tasks in the set of tasks with reference values for the server system to detect changes in performance of the server system.
 21. The computer-readable media of claim 20, the operations further comprising determining, for each of the tasks in the set of tasks, a baseline level of performance of the server system for the task based on performance of the server system for each of multiple previous instances of the server system performing the task; wherein comparing the sets of performance measures with the reference values comprises comparing, for each of the sets of performance measures, the performance measure for each task with the corresponding baseline level of performance for the task. 